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Update the folder titles for targets in the monorepository that have not seen taken care of for some time. These are the folders that targets are organized in Visual Studio and XCode (`set_property(TARGET <target> PROPERTY FOLDER "<title>")`) when using the respective CMake's IDE generator. * Ensure that every target is in a folder * Use a folder hierarchy with each LLVM subproject as a top-level folder * Use consistent folder names between subprojects * When using target-creating functions from AddLLVM.cmake, automatically deduce the folder. This reduces the number of `set_property`/`set_target_property`, but are still necessary when `add_custom_target`, `add_executable`, `add_library`, etc. are used. A LLVM_SUBPROJECT_TITLE definition is used for that in each subproject's root CMakeLists.txt.
Flang
Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.
Please note that flang is not ready yet for production usage.
Getting Started
Read more about flang in the docs directory. Start with the compiler overview.
To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.
Treatment of language extensions is covered in this document.
To understand the compilers handling of intrinsics, see the discussion of intrinsics.
To understand how a flang program communicates with libraries at runtime, see the discussion of runtime descriptors.
If you're interested in contributing to the compiler, read the style guide and also review how flang uses modern C++ features.
If you are interested in writing new documentation, follow LLVM's Markdown style guide.
Consult the Getting Started with Flang for information on building and running flang.